ID CYB_GENJO Reviewed; 379 AA. AC Q6XBW5; DT 31-OCT-2006, integrated into UniProtKB/Swiss-Prot. DT 05-JUL-2004, sequence version 1. DT 24-JAN-2024, entry version 72. DE RecName: Full=Cytochrome b; DE AltName: Full=Complex III subunit 3; DE AltName: Full=Complex III subunit III; DE AltName: Full=Cytochrome b-c1 complex subunit 3; DE AltName: Full=Ubiquinol-cytochrome-c reductase complex cytochrome b subunit; GN Name=MT-CYB; Synonyms=COB, CYTB, MTCYB; OS Genetta johnstoni (Johnston's genet). OG Mitochondrion. OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; OC Eutheria; Laurasiatheria; Carnivora; Feliformia; Viverridae; Viverrinae; OC Genetta. OX NCBI_TaxID=205594; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RA Gaubert P., Fernandes C.A., Bruford M.W., Veron G.; RT "Genets (Carnivora, Viverridae) in Africa: an evolutionary synthesis based RT on cytochrome b sequences and morphological characters."; RL Biol. J. Linn. Soc. Lond. 81:589-610(2004). RN [2] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RA Gaubert P., Tranier M., Delmas A.-S., Colyn M., Veron G.; RT "First molecular evidence for reassessing phylogenetic affinities between RT genets (Genetta) and the enigmatic genet-like taxa Osbornictis, Poiana and RT Prionodon (Carnivora, Viverridae)."; RL Zool. Scr. 33:117-129(2004). CC -!- FUNCTION: Component of the ubiquinol-cytochrome c reductase complex CC (complex III or cytochrome b-c1 complex) that is part of the CC mitochondrial respiratory chain. The b-c1 complex mediates electron CC transfer from ubiquinol to cytochrome c. Contributes to the generation CC of a proton gradient across the mitochondrial membrane that is then CC used for ATP synthesis. {ECO:0000250|UniProtKB:P00157}. CC -!- COFACTOR: CC Name=heme b; Xref=ChEBI:CHEBI:60344; CC Evidence={ECO:0000250|UniProtKB:P00157}; CC Note=Binds 2 heme b groups non-covalently. CC {ECO:0000250|UniProtKB:P00157}; CC -!- SUBUNIT: The cytochrome bc1 complex contains 11 subunits: 3 respiratory CC subunits (MT-CYB, CYC1 and UQCRFS1), 2 core proteins (UQCRC1 and CC UQCRC2) and 6 low-molecular weight proteins (UQCRH/QCR6, UQCRB/QCR7, CC UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and a cleavage product of CC UQCRFS1). This cytochrome bc1 complex then forms a dimer. CC {ECO:0000250|UniProtKB:P00157}. CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane CC {ECO:0000250|UniProtKB:P00157}; Multi-pass membrane protein CC {ECO:0000250|UniProtKB:P00157}. CC -!- MISCELLANEOUS: Heme 1 (or BL or b562) is low-potential and absorbs at CC about 562 nm, and heme 2 (or BH or b566) is high-potential and absorbs CC at about 566 nm. {ECO:0000250}. CC -!- SIMILARITY: Belongs to the cytochrome b family. {ECO:0000255|PROSITE- CC ProRule:PRU00967, ECO:0000255|PROSITE-ProRule:PRU00968}. CC -!- CAUTION: The full-length protein contains only eight transmembrane CC helices, not nine as predicted by bioinformatics tools. CC {ECO:0000250|UniProtKB:P00157}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; AY241892; AAP73012.1; -; Genomic_DNA. DR EMBL; AF511051; AAQ08027.1; -; Genomic_DNA. DR AlphaFoldDB; Q6XBW5; -. DR SMR; Q6XBW5; -. DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell. DR GO; GO:0045275; C:respiratory chain complex III; IEA:InterPro. DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW. DR GO; GO:0008121; F:ubiquinol-cytochrome-c reductase activity; IEA:InterPro. DR GO; GO:0022904; P:respiratory electron transport chain; IEA:InterPro. DR CDD; cd00290; cytochrome_b_C; 1. DR CDD; cd00284; Cytochrome_b_N; 1. DR InterPro; IPR005798; Cyt_b/b6_C. DR InterPro; IPR036150; Cyt_b/b6_C_sf. DR InterPro; IPR005797; Cyt_b/b6_N. DR InterPro; IPR027387; Cytb/b6-like_sf. DR InterPro; IPR030689; Cytochrome_b. DR InterPro; IPR048260; Cytochrome_b_C_euk/bac. DR InterPro; IPR048259; Cytochrome_b_N_euk/bac. DR InterPro; IPR016174; Di-haem_cyt_TM. DR PANTHER; PTHR19271; CYTOCHROME B; 1. DR PANTHER; PTHR19271:SF37; CYTOCHROME B; 1. DR Pfam; PF00032; Cytochrom_B_C; 1. DR Pfam; PF00033; Cytochrome_B; 1. DR PIRSF; PIRSF038885; COB; 1. DR SUPFAM; SSF81648; a domain/subunit of cytochrome bc1 complex (Ubiquinol-cytochrome c reductase); 1. DR SUPFAM; SSF81342; Transmembrane di-heme cytochromes; 1. DR PROSITE; PS51003; CYTB_CTER; 1. DR PROSITE; PS51002; CYTB_NTER; 1. PE 3: Inferred from homology; KW Electron transport; Heme; Iron; Membrane; Metal-binding; Mitochondrion; KW Mitochondrion inner membrane; Respiratory chain; Transmembrane; KW Transmembrane helix; Transport; Ubiquinone. FT CHAIN 1..379 FT /note="Cytochrome b" FT /id="PRO_0000254693" FT TRANSMEM 33..53 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 77..98 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 113..133 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 178..198 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 226..246 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 288..308 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 320..340 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT TRANSMEM 347..367 FT /note="Helical" FT /evidence="ECO:0000250|UniProtKB:P00157" FT BINDING 83 FT /ligand="heme b" FT /ligand_id="ChEBI:CHEBI:60344" FT /ligand_label="b562" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000250|UniProtKB:P00157" FT BINDING 97 FT /ligand="heme b" FT /ligand_id="ChEBI:CHEBI:60344" FT /ligand_label="b566" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000250|UniProtKB:P00157" FT BINDING 182 FT /ligand="heme b" FT /ligand_id="ChEBI:CHEBI:60344" FT /ligand_label="b562" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000250|UniProtKB:P00157" FT BINDING 196 FT /ligand="heme b" FT /ligand_id="ChEBI:CHEBI:60344" FT /ligand_label="b566" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000250|UniProtKB:P00157" FT BINDING 201 FT /ligand="a ubiquinone" FT /ligand_id="ChEBI:CHEBI:16389" FT /evidence="ECO:0000250|UniProtKB:P00157" SQ SEQUENCE 379 AA; 42713 MW; E836C5FE03D94932 CRC64; MTDIRKSHPL AKIINESFID LPAPSNISAW WNFGSLLGVC LIIQILTGLF LAMHYTSDTM TAFSSVTHIC RDVNYGWIIR YMHANGASMF FICLFMHAGR GVYYGSYTFT ETWNIGILLM FTVMATAFMG YVLPWGQMSF WGATVITNLL SAIPYIGTNL VEWIWGGFSV DKATLTRLFA FHFILPFIIS ALAAVHLLFL HETGSNNPSG MMSDSDKIPF HPYYTIKDIL GILLLILVLM LLVLFSPDLL GDPDNYIPAN PLNTPPHIKP EWYFLFAYAI LRSIPNKLGG VLALVLSILI LAIIPFLHTS KQRSMMFRPL SQCLFWLLVA DLLTLTWIGG QPVEHPFITI GQLASILYFS IFLILMPVSG IIENRLLKW //